Wireless communications systems, for example packet data communications systems, may utilize shared channels wherein the network allocates resources to a mobile station for uplink transmissions based on the number of mobiles requesting resources, the channel conditions of the mobile station, and the services for which the mobile station is requesting resources.
The mobile station will transmit information to the network regarding a buffer status of each radio bearer or for a group of radio bearers. Typically each service utilized by the mobile station is mapped to one radio bearer. Each service and thus, each radio bearer, is associated with a priority. In order to minimize the amount of signaling overhead, it is preferred to have a mobile station indicate the amount of data in its buffer across all radio bearers and indicate for example, the highest priority radio bearer that has data waiting to be sent. This allows the network to assign resources with some degree of fairness.
The buffer status information, which may be referred to as scheduling information (SI), may be transmitted by the mobile over an uplink control channel that terminates effectively in layer 1 or Medium Access Control (MAC) layer, or as piggy back information to the network over a shared data channel. So-called piggy back information is scheduling and/or control information, which may be segmented, and added to data packets being transmitted on a data channel.
The data transmitted over the shared data channel is transmitted using parallel Hybrid Automatic Repeat Request (HARQ) channels or processes. However, the HARQ mechanism implies that data packets, which may have piggy backed scheduling and/or control information, may be received by the network out-of-sequence. This is particularly true in the case where the control information, which is common across all IP flows, is appended to data packets associated with one of the IP flows. In this case, the sequence number associated with the data packets cannot be used to sequence the control information. Thus, for example, scheduling information may not be received at the relevant time, or if segmented, may be received, and possibly applied, in an incorrect order.
Therefore, although the network has a mechanism for determining the correct order of segmented data received in out-of-order packets, the scheduler at the network cannot discern the order of piggy backed information and may then schedule the mobile on the basis of incorrect information.
Further, various rules may be applied to allow the mobile to send SI on a periodic basis or on an event triggered basis, which may result in quite rapid sequential SI transmissions.
Thus, there is a need for apparatuses and methods for indicating a sequence order of scheduling and/or control information where the scheduling and/or control information is included in packets having sequence numbers that are not necessarily related to the sequence of included scheduling and/or control information.